//
//  SocketEngineSpec.swift
//  QHSocketIODemo
//
//  Created by chen on 2017/5/15.
//  Copyright © 2017年 chen. All rights reserved.
//

import Foundation

@objc public protocol SocketEngineSpec {
    weak var client: SocketEngineClient? { get set }
    var closed: Bool { get }
    var connected: Bool { get }
    var connectParams: [String: Any]? { get set }
    var doubleEncodeUTF8: Bool { get }
    var cookies: [HTTPCookie]? { get }
    var extraHeaders: [String: String]? { get }
    var fastUpgrade: Bool { get }
    var forcePolling: Bool { get }
    var forceWebsockets: Bool { get }
    var parseQueue: DispatchQueue { get }
    var polling: Bool { get }
    var probing: Bool { get }
    var emitQueue: DispatchQueue { get }
    var handleQueue: DispatchQueue { get }
    var sid: String { get }
    var socketPath: String { get }
    var urlPolling: URL { get }
    var urlWebSocket: URL { get }
    var websocket: Bool { get }
    var ws: WebSocket? { get }
    
    init(client: SocketEngineClient, url: URL, options: NSDictionary?)
    
    func connect()
    func didError(reason: String)
    func disconnect(reason: String)
    func doFastUpgrade()
    func flushWaitingForPostToWebSocket()
    func parseEngineData(_ data: Data)
    func parseEngineMessage(_ message: String, fromPolling: Bool)
    func write(_ msg: String, withType type: SocketEnginePacketType, withData data: [Data])
}

extension SocketEngineSpec {
    var urlPollingWithSid: URL {
        var com = URLComponents(url: urlPolling, resolvingAgainstBaseURL: false)!
        com.percentEncodedQuery = com.percentEncodedQuery! + (sid == "" ? "" : "&sid=\(sid.urlEncode()!)")
        
        return com.url!
    }
    
    var urlWebSocketWithSid: URL {
        var com = URLComponents(url: urlWebSocket, resolvingAgainstBaseURL: false)!
        com.percentEncodedQuery = com.percentEncodedQuery! + (sid == "" ? "" : "&sid=\(sid.urlEncode()!)")
        
        return com.url!
    }
    
    func createBinaryDataForSend(using data: Data) -> Either<Data, String> {
        if websocket {
            var byteArray = [UInt8](repeating: 0x4, count: 1)
            let mutData = NSMutableData(bytes: &byteArray, length: 1)
            
            mutData.append(data)
            
            return .left(mutData as Data)
        } else {
            let str = "b4" + data.base64EncodedString(options: Data.Base64EncodingOptions(rawValue: 0))
            
            return .right(str)
        }
    }
    
    func doubleEncodeUTF8(_ string: String) -> String {
        if let latin1 = string.data(using: String.Encoding.utf8),
            let utf8 = NSString(data: latin1, encoding: String.Encoding.isoLatin1.rawValue) {
            return utf8 as String
        } else {
            return string
        }
    }
    
    func fixDoubleUTF8(_ string: String) -> String {
        if let utf8 = string.data(using: String.Encoding.isoLatin1),
            let latin1 = NSString(data: utf8, encoding: String.Encoding.utf8.rawValue) {
            return latin1 as String
        } else {
            return string
        }
    }
    
    /// Send an engine message (4)
    func send(_ msg: String, withData datas: [Data]) {
        write(msg, withType: .message, withData: datas)
    }
}
